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The hydrological characteristics of roto-translational slides in flysch are complex, due to the inherent anisotropy and heterogeneity of rock masses and related deposits. The paper deals with the hydrogeological characterization of a reactivated roto-translational slide affecting Cretaceous flysch rocks, located in the northern Apennines of Italy. Continuous monitoring of groundwater levels, in-situ permeability and pumping tests, hydrochemical analyses and uranine tracers were the adopted prospecting methods. Results showed that two overlaying aquifers exist at the slope scale: the first is unconfined, but highly compartmentalized, and hosted in the fractured and dismembered rock slide body. The second is confined and pressurized and lays in the undisturbed flysch below the sliding surface. The latter is therefore a relevant factor for the instability of the slope. In this work, hydrologic monitoring and investigation are summarized, in order to support the anal-ysis of landslide trigger mechanisms and to identify and design proper drainage system.

The Ca’ Lita landslide is a large and deep-seated mass movement located in the northern Apennines of Italy. It consists of a complex-composite landslide that affects Cretaceous to Eocene flysch rock masses and chaotic complexes. The landslide head zone resumed activity in 2002 and in 2004 the landslide was totally reactivated. More than 50 m retrogression of the scarp, and about 400 m advancement of the toe threatened villages and an important road connecting several key industrial facilities located in the upper watershed. A national state of emergency was declared by the Authorities, following the evolution of 2004. A large plan of civil protection interventions was implemented, aimed at the management of risk and at the identification and realisation of structural mitigation. The Ca’ Lita landslide is a noticeable case history both from the geomorphic and the risk management perspectives. The relatively fast evolution undergone by the phenomenon from 2002 to date, and the remarkable advancement of the toe, point out that total and partial reactivations of dormant landslides can cause unexpected consequences in terms of involvement of new areas that, in practice, have no previous hazard rating assigned. Also, the landslide is a test bed for coupled monitoring and mitigation actions that, in a relatively short time, have allowed passing from response, to mitigation and preparedness phases. In this work, the management of the emergency is presented in the frame of monitoring, mitigation and modelling activities that are the result of the shared effort of public offices and research institutes.

Analisi della prospettiva europeista nella produzione scientifica di Raymond Aron.

From the beginning of the Great Recession (2008), the issue of European integration acquired increasing salience in many European polities. Extremist and niche parties have been the main agents of the politicization of the European issue; accordingly, mainstream parties have been forced to deal with a crisis of legitimacy of the European project. This chapter sheds light on the radical left (RLPs) and social democratic (SDPs) party families, that have had historically divergent positions on the EU: RLPs have been more sensitive to the issue of a social Europe and have opposed an integration of the EU dominated by neoliberal logic, thus coming to be defined as a Eurosceptic party family; SDPs, on the other hand, have been supportive of EU integration and of the European Social Model. The main research question is the following: to what extent do SDPs and RLPs still diverge in the political and socio-economic field with regard to the European Union? Through the comparison of the Spanish and the Italian cases the chapter concludes that: the crisis brought SDPs closer to a functional Europeanism, while the RLPs Eurocritical pre-crisis position was strengthened; while SDPs have moved leftward vis-à-vis the social Europe issue, the economic and political issues are still divisive for the two families.

Rapid assessment of landslide activity is important in case of adverse climatic conditions leading to civil protection’s alerts that require increased surveillance of risk areas. GB-InSAR is nowadays becoming a consolidated near-sensing monitoring technique for slope movements. It can be installed rapidly and it can rapidly provide results in the form of displacement maps. However, it has never been thoroughly tested in radar-hostile conditions such as these posed by large-scale earth slides – earth flows covered by a canopy of trees bushes and meadows, that are the typical landslides in Emilia Romagna Apennine. As sparse small villages, buildings, roads and other lifelines are often built on these landslide bodies, they are of particular concern for civil protection, especially during prolonged rainfall periods that determine attention/alerting conditions. To test the possibility to achieve improved surveillance capability in case of attention needed, a series of GB-InSAR spot campaigns lasting from a week to a month, was carried out in 2010–11 in several landslides of Emilia Romagna Apennine using a commercial interferometric radar. The aim was to evaluate the performance of the technique for rapid assessment of landslide activity, even in case of partly vegetated soil coverage conditions. The paper deals with the results obtained in 3 out of the 11 monitored sites.

International audience; The Ca' Lita landslide is a large and deep-seated mass movement located in the Secchia River Valley, in the sector of the Northern Apennines falling into Reggio Emilia Province, about 70 km west of Bologna (Northern Italy). It consists of a composite landslide system that affects Cretaceous to Eocene flysch rock masses and chaotic complexes. Many of the components making up the landslide system have resumed activity between 2002 and 2004, and are now threatening some hamlets and an important road serving the upper watershed area of River Secchia, where many villages and key industrial facilities are located. This paper presents the analysis and the quantification of displacement rates and depths of the mass movements, based on geological and geomorphological surveys, differential DEM analysis, interpretation of underground stratigraphic and monitoring data collected during the investigation campaign that has been undertaken in order to design cost-effective mitigation structures, and that has been conducted with the joint collaboration between public offices and research institutes.

This case study paper is about a large rotational rock and earth slide—earth flow located in the Secchia River Valley, in the Northern Apennines of Italy, that has displayed multiple reactivation phases between 2002 and 2004. The main geological constraints of the mass movement are related to the overlap of flysch rock masses over clayey complexes that allows rock slides to take place in the source area. The disarrangement and weathering of rock masses following slope movements causes large amount of fine-grained debris to be accumulated on the slope and mobilised by earth sliding and flowing. Analysis of rainfall data at the onset of reactivation events has proved that they occurred after periods with cumulated values higher than the averages of the last 30 years. The quantification of the morphological modifications induced by these reactivations has been made possible by comparing pre- and post-event digital elevation models. Depletion and accumulation has been in the range of 30 m in different parts of the slope. In particular, an advancement of the landslide toe of more than 400 m, which caused a 30-m thick landslide tip to deposit, has been clearly seen. Monitoring data regarding subsurface movements and surface tension crack widening (tension cracks so large as to be properly described at trenches) has shown that sliding surfaces as deep as 43 m exist in the upper part of the landslide, while the accumulation lobe has moved by sliding and flowing over surfaces as deep as some 10 m. Velocities of cm/day have been recorded in the deep surfaces and in widening trenches of the source area, while the advancement of the accumulation lobe has been estimated as having velocities of up to 10 m/day. Groundwater in the landslide body has been observed at depths of 5–15 m in the upper areas, while it is estimated as being at the ground level in the toe. On this basis, it is concluded that the landslide still has a high potential for further development, both in the upper landslide zone and in the toe area.